char* -> NSString 로 NSString -> char* 로 변환 하는 방법.

char* -> NSString

char szText[] = "hi...";

NSString* nsStr = [NSString stringWithUTF8String: szText];

char strDocumentDirectory[1024];
[pDocumentsDirectory getCString:strDocumentDirectory maxLength:sizeof(strDocumentDirectory)-1 encoding:NSASCIIStringEncoding];

NSString -> char*

NSString* nsStr = @"hi I'm NSString";

const char* strTmp = [nsStr UTF8String];

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